Design Team 10
ECE 480 FS08
Progress Report 2
Battery-Supercapacitor Hybrid Energy Storage System
Since the last progress report, we have been ordering the parts needed for the project and
thinking about different designs. There were four proposed designs for delivering power to a
pulsating load:
1) Using just supercapacitors
2) Using just batteries
3) A hybrid system using both batteries and supercapacitors in parallel.
4) A hybrid system using both batteries and supercapacitors with active circuit components
between the two.
The first system would require too many supercapacitors. The second system is the current
technology in use. The third system would reduce battery size, but would need more than three
supercapacitor modules, which cost over $2200 apiece. It also requires the battery &
supercapacitor module to have the same voltage level, limiting its effectiveness. The fourth
system has the most potential because it utilizes modern semiconductor technology to address
the problems inherent in the system three design.
Battery:
The team purchased 14 lithium polymer (Li-PO) battery cells, each rated at 3.7 volts and 21
Amp hours. These cells will be connected in series to yield a total of 51.8V. We chose to use 14
cells because of the difficulty associated with obtaining a 13 cell, 48.1V PCM. Since we are
building the fourth system, active components will compensate for the voltage difference
between the 48.6V supercapacitor and the 51.8V (nominal) battery. The PCM supplier was out
of stock of the battery fuel gauges used with the particular PCM we selected. We are currently
researching other means to determine and display the energy level in real-time.
Supercapacitor:
The team purchased a 165F super capacitor module from Maxwell Technologies. Their 83F
module would have been capable of meeting our parameters however, the supplier did not have
this module in stock and estimated a six week wait. Obviously this was not compatible with the
semester time frame and our design schedule. Instead, we purchased the 165F module which
cost approximately $600 more than the 83F module. Our prototype hybrid system will utilize
high current, solid state relays to disconnect certain elements from the circuit, such as the battery,
at opportune times during the operating cycle, corresponding with the power demand of the load.
This will allow the system to take advantage of the high power density of the supercapacitors and
shield the battery form the damaging effects of short, instantaneous bursts of increased load
demand. Once the load demand levels off and returns to normal, the battery will be reconnected
to the circuit, recharging the supercapacitors at a slower rate than they were discharged. This
takes advantage of the batteries high energy density and prepares the system for the next spike in
load demand. Because this system isolates the battery from the supercapacitor module and then
reintroduces it, the supercapacitors charge, partially discharge and then recharge making the
system require only one Supercapacitor module. Given the same discharge time period and load,
the 165F supercapacitor module will discharge a lower percentage of its total charge compared to
the 83F module. This means that the voltage drop experienced as the supercapacitors discharge
will be reduced, potentially increasing system performance and allowing it to exceed the
project’s minimum parameters.
Design Team 10
ECE 480 FS08
Progress Report 2
Load:
The team has ordered the components necessary to build a basic, programmable, pulsating
load of 2.5Ω. Using a Millennium 3 programmable relay controller, high current, conventional
relays, and two 1kW rated 5Ω resistors connected in parallel, the team will construct the basic
load required. Once the entire system is assembled, it will be tested on this rudimentary load.
Subsequent improvements will be made, such as adding more resistors and relays and having
some element of the load which can be visually verified.
Budget:
We have currently used just under half of our $10,000 budget.
Part #
Model
Prototype
Ultracapacitors
ESHSR-0010C0002R7
BMOD0165
Item/Info
NessCap Co Ltd
Maxwell Technologies BMOD016548.6V
PCMs
Model
PCM-B03S10-188
Prototype
PCM-L14S40-232
PCM,Equilibrium Function, 3 cell LiIon/PO
PCM with Equilibrium function for 14 LiIon Cells
Batteries
Prototype
Model
F
ESR
mOhm
15
$3.25
2.70
10.00
35.00
1
$2,240.00
48.10
165.00
7.10
Sub Total:
$2,288.68
QTY
$
V
A Limit
1
$13.32
11.10
10.00
1
$99.95
51.80
40.00
Sub Total:
$113.27
QTY
$
V
A/H
ESR
mOhm
14.00
$94.00
3.70
42.00
PL-6045135U
Hi-Power Polymer Li-Ion Cell
3
$17.50
3.70
3.00
Sub Total:
$1,368.50
QTY
$
V
Connection
1
$119.85
3.70
USB
Sub Total:
$119.85
QTY
$
Ω
W
V
2
$149.56
5.00
1000.00
70.711
Sub Total:
$299.12
QTY
$
V
AWG
A
CBA-II
Computerized Battery Analyzer
TA1K0PH5R00KE
Ohmite, Thick Film
PCB-3GS-1
Fuel Gauge, PCB of 11.1v Battery Pack
1
$7.95
11.10
Prototype
CN-SA2
Anderson Connector
3
$9.99
8"
Prototype
D1D40
Solid State Relay (SSR)
4
$65.22
100.00
40.00
Prototype
G8P-1A2T-F-DC24
10
$3.36
250.00
30.00
Prototype
88970084
Relay, PWR SPST, 24V Coil
START KIT LOGIC CNTRL XD26
24VDC
1
$277.00
24.00
Sub Total:
$609.43
TOTAL:
12.00
OD
22
Oct
11
Nov
22
Oct
5
Nov
14
Miscellaneous
Model
V
Polymer Li-Ion Cell: (2C) rate
Resistors
Prototype
$
1055275 UL listed
Battery Analyzer
Both
QTY
40.00
5
Nov
22
Oct
22
Oct
14
Nov
22
Oct
5
Nov
14
Nov
14
Nov
14
Nov
$4,798.85
Shipping:
$45.90
Grand
Total
$4,844.75
* Shipping for items ordered November
11th or later is not included in this total.
Design Team 10
ECE 480 FS08
Progress Report 2
Gant Chart